Validity and reproducibility of a whole‐room indirect calorimeter for the estimation of VO2, VCO2, and resting metabolic rate. Issue 7 (5th April 2023)

• Record Type: Journal Article
• Authors: Henriksen, Hege Berg; Henriksen, Christine; de Sousa, Ana Rita Sequeira; Alavi, Dena Treider; Augestad, Elin Maria Sandstad; Rising, Russell; Dörner, Rebecca; Hägele, Franziska Anna; Bosy‐Westphal, Anja; Blomhoff, Rune; Ulven, Stine Marie; Olsen, Thomas
• Is Part Of: Physiological reports. Volume 11:Issue 7(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-04-05
• Subjects: energy expenditure -- metabolism -- resting metabolic rate -- whole‐room indirect calorimetry; Physiology -- Periodicals; 571
• DOI: 10.14814/phy2.15658
• Languages: English
• ISSNs: 2051-817X

Abstract

Abstract: Whole‐room indirect calorimeters (WRICs) provide accurate instruments for the measurement of respiratory exchange, energy expenditure, and macronutrient oxidation. Here, we aimed to determine the validity and reproducibility of a 7500 L WRIC for the measurement of ventilation rates and resting metabolic rate (RMR). Technical validation was performed with propane combustion tests ( n = 10) whereas biological reproducibility was tested in healthy subjects (13 women, 6 men, mean ± SD age 39.6 ± 15.3) in two 60 min measurements separated by 24 h. Subjects followed a run‐in protocol prior to measurements. The coefficient of variation (CV) and intraclass correlation coefficient (ICC) were calculated for ventilation rates of O2 (VO2), CO2 (VCO2), the respiratory quotient (RQ; VCO2/VO2), and RMR. Technical validation showed good validity with CVs ranging from 0.67% for VO2 to 1.00% for energy expenditure. For biological reproducibility, CVs were 2.89% for VO2 ; 2.67% for VCO2 ; 1.95% for RQ; and 2.68% for RMR. With the exception of RQ (74%), ICCs were excellent for VO2 (94%), VCO2 (96%) and RMR (95%). Excluding participants that deviated from the run‐in protocol did not alter results. In conclusion, the 7500 L WRIC is technically valid and reproducible for ventilation rates and RMR. Abstract : Whole‐room indirect calorimetry is an accurate method for measuring metabolic rates. Here, we report that a newly built whole‐room indirect calorimeter at the Department of Nutrition, University of Oslo provides valid and reproducible measurements of resting metabolic rate.